Device for automatic feed of cutting bit in well drilling



Nov. 3, 1964 v. s. KAZMIN ETAL 3,155,172

DEVICE FOR AUTOMATIC FEED 0F CUTTING BIT IN WELL DRILLING Filed April 13, 1961 3 Sheets-Sheet 1 INVENTORS M 6" KAzM/A/ M 4/. KOMHBOV If M Kuoerflsflov 5. 6. AN rum/0 v BY 141 M ATTORNEYS 3, 1954 v. s. KAZMIN ETAL 3,155,172

DEVICE FOR AUTOMATIC FEED OF CUTTING BIT IN WELL DRILLING Filed April 15, 1961 3 Sheets-Sheet 2 INVENTORS BY Ja /4 W; $1M

ATTORNEYS Nov. 3, 1964 3,155,172

DEVICE FOR AUTOMATIC FEED OF CUTTING BIT IN WELL. DRILLING v. s. KAZMIN ETAL 3 Sheets-Sheet 3 Filed April 13, 1961 INVENTORS K (/02 YH8H0 v ANT-0M0 v ATTORNEYS United States Patent 3,155,172 DEVICE FER AUTGMATiC FEED 9F CUTTING BET 1N WELL DRELLENG Vadim Sergueievich Kazmin, Krasnaia Presnia 9, Apt. 105; Vladimir Nicholaievich Komarov, Kalyaievslraya 35, Apt. 3; Ivan Nickolaievich Kudryashov, Bolshaia Polianka 42/2, Apt. 21; and Boris gernionovich Antonov, Varshavslroie Charisse 35h, Korpns 4, Apt. 4, all of Moscow, USSR.

Filed Apr. 13, 1961, Ser. No. 134,484 7 Claims. (Cl. 1736) The present invention relates to a device for automatic feed of a cutting bit in well drilling.

A disadvantage of known prior art devices of this type lies in the fact that the rate of feed of the drilling tool is independent of the torque applied to the bit.

The apparatus of this invention provides for cutting bit feed control based on two conditions, one being the axial force applied to the cutting bit, and the other being the torque applied to the bit which is determined by means of a pivotaliy movable reduction gear driving the rotary table. The reactive torque of the latter is transferred through the housing of the reduction gear to the piston of a hydraulic transmitter which controls the operation of a combination motor-pump.

The lifting of the drilling tool is achieved by forcing the liquid agent into the motor-pump and by reversing rotation of the reduction gear, or by the electric motor connected to the above reduction gear and started by an electric relay the control contacts of which are closed by the piston of the hydraulic transmitter.

It is accordingly the object of this invention to provide an apparatus for controlling the feed of a drill bit in a well in response to both the axial force and torque applied to the drill bit.

Further objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a diagrammatic view showing a drill feed controlling apparatus constructed in acocrdance with one form of this invention;

FIG. 2, a sectional view showing a planetary gear reduction drive for the rotary table of a well drilling rig, the housing of the reduction gear being mounted for pivotal movement;

FIG. 3, a side elevational view with parts in section showing the reduction gear of FIG. 2, and a hydraulic transmitter forming part of the control apparatus;

FIG. 4, a diagrammatic view similar to FIG. 1 but showing a modified form of the invention; and,

FIG. 5, a diagrammatic view similar to FIG. 1, but showing a still further modified form of the invention.

FIG. 1 shows the cutting bit 1 being rotated by the rotary table 4 through the drill string 2 and the square bar 3. The entire unit is suspended from a hoisting block system 5 through a swivel 6.

The steel cable 7 of the block system 5 is wound on the drum 8 which rotates the motor-pump 11 under the action of the weight of the drilling unit transmitted through the chain drive 9 and reduction gear 11). Liquid is pumped by the motor-pump from the tank 12 through the pipe 13 and is forced through the pipeline 14- through the port A into the control device 15 where it flows through the recess in the valve 16 and then through the pipeline 17 to the valve 18 urged into engagement with a seat by the screw 19 and spring 20. The liquid forced through the valve 18 and through the pipe 21 returns to the tank 12 through the control device 15 and the discharge pipe 22.

The continuously running pump 23 takes liquid from the same tank 12 and pumps it through the pipe 24 into the control device 15. Until the port 25 in the control 3,155,172 Patented Nov. 3, 1964 "Ice device 15 is closed by the valve 16, the liquid passes through the body of the control device 15 and returns to the tank through the discharge pipe 22. If the valve 16 completely closes the port 25, the relief valve 26 opens, and the liquid flows through the pipe 14 into the inlet of the motor-pump 11 which drives the reduction gear 1d, chain drive 9, drum 8 and the hoisting block system 5 thus lifting the drilling unit.

The combination motor-pump is a reversible apparatus, which operates as a pump when its shaft is driven, and as a motor when the liquid is forced into it.

The movement of the valve 16 inside the body of the control vdevice 15 depends on the pressure in the pipe 27 which is determined by the degree of torque applied to the rotary table 4. The table 4 is driven through the bevel pinion 28 by the planetary reduction gear 29, as shown in PEG. 2, which pivots around shafts 30 and 31, and the lug 32 transmits the reactive torque of the reduction gear 29 by means of the rod 33 to the piston 34, disposed in the cylinder 35 of a hydraulic transmitter, which operates to increase or decrease the pressure in the pipe 27.

When drilling is performed by means of an electric drive, as shown in FIG. 4, the core 36 of a solenoid 37 connected to the circuit of the electric drive actuates the piston 38 in the cylinder 39 of a hydraulic transmitter to provide for a change in pressure in the pipe 27 depending on the torque applied to the cutting bit.

A third version of the device for lifting the drilling unit is shown in FIGURE 5 and is provided in the form of a hydraulic relay 40 which is actuated by the pressure in the pipe 27 and thus actuates the contacts 41 controlling the magnetic starter 42 of the electric motor 43 coupled to the drive shaft of the reduction gear 10. In this form of the invention the pump 23, the relief valve 26, pipe 24 and the port 25 can be eliminated. The electric motor 43 may, if desired, be replaced by a pneumatic motor and in this case the hydraulic relay 40 closes the contacts of an electro-pneumatic valve of the pneumatic motor control (not shown in the drawing).

Maintenance of constant pressure of the drill bit 1 against the well bottom is provided as follows. The drum 8 or" the hoisting means loaded by the weight of the drilling unit through the cable 7 of the block system 5, rotates the motor-pump 11 by means of the chain drive 9 and reduction gear 11). The motor-pump forces liquid through the pipelines 14 and 17 to the valve 18 adjusted for a predetermined pressure in the pipelines. This pressure determines the load on the pump 11 which, by a. braking action, controls the rotation of the drum 8.

If the pressure of the spring 219 exceeds the pressure created by the liquid on the valve 18, then the liquid will fail to open the valve and the motor-pump 11 will stop, as a result of which downward movement of the drilling unit will stop.

The above described system of pressure control enables pressure of the drill bit against the rock face to be maintained constant and predetermined irrespective of the drilling speed, i.e. the speed of drilling will be automatically increased when the cutting bit encounters better drilling conditions (soft rock), or automatically decreased when it encounters harder conditions (hard rock),

The maintenance of constant torque of the cutting bit in rotary drilling is achieved as follows: the reactive torque of the reduction gear 29 actuates the piston 34 through the lug 32 and rod 33, and thus forces liquid out of the cylinder 35 through the pipe 27 to the valve 16 which results in moving the latter inside the cylinder of the control device 15, in an axial direction, but when the pressure reaches a certain limit in the pipe 27 the valve starts closing the port A which results in braking the motor-pump 11 and decreasing the downward movement of the drilling unit, and when the port A is completely closed the feed comes to a standstill.

The closing of the port A by the valve 16 is equal to increasing the pressure of the spring 2% on the ball valve 18.

Since the pressure in the pipeline 27 is in direct proportion to the torque applied to the cutting bit, a constant torque at the cutting bit can be maintained by adjusting the spring of the control device 15 for a certain pressure.

If port A is completely closed by the valve 36 and downward movement of the drilling unit is stopped, but the torque applied to the drill bit 1 is still increasing, then the valve 16 moving further in the axial direction, will completely close the opening 25, and the liquid forced by the pump 23 through the relief valve 26 will be forced into the motor-pump 11 to bring about its reverse rotation and lifting of the drilling unit until the torque is decreased to the predetermined value.

The decrease of torque leads to lowering of pressure in the pipe 27, as a result of which the spring in the control device 15 will bring the valve In back to its initial position, and drilling will proceed in a normal manner.

When drilling with an electric drive the determining characteristic is not the torque applied to the rotary table, but the value of the electric current carried by the winding of the electric drive motor.

Since the solenoid 37 is connected to the circuit of the electric drive motor, the magnetic force in the core Ed is in direct proportion to the value of the torque applied to the drill bit and, consequently, the pressure created by the piston 38 inside the cylinder 39 and transferred to the valve 16 of the control device 15 is also in direct proportion to the torque applied to the drill bit. The control of the torque is provided in the same way as described in the case of the other drive means.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the inven tion is not limited by that which is shown in the drawings and described in the specification, but only as indicated in the appended claims.

What is claimed is:

1. In a well drilling apparatus including a drill bit carried by a drill string, a rotary table for driving the drill string and means including a hoisting drum for raising and lowering the drill string, an apparatus for controlling the feed of the drill string in accordance with the force of gravity and the torque applied to the drill string through the rotary table, said control apparatus comprising a combination motor-pump drivingly connected to said drum and having an intake and discharge, a liquid tank connected to said intake, a pressure responsive hydraulic control device connected to said discharge and having an open and closed position, resilient means to bias said control device to open position, a pressure responsive valve connected to said control device through an inlet and outlet, said control device in open position providing communication between said discharge and said inlet to said pressure responsive valve, a return pipe from said control device to said tank, a pump connected to said tank providing a hydraulic pressure source, a conduit connecting said source and said control device, a relief valve connected between said conduit and said discharge, said control device in closed position serving to close said conduit, whereby the resulting increased pressure in said conduit opens said relief valve to provide communication be tween said conduit and said discharge, a planetary reduction gear for driving said rotary table, said reduction gear having a housing mounted for pivotal movement, a hydraulic transmitter actuated by movement of said housing and a pipe connecting said transmitter and said control device, operation of said transmitter serving to move said control device to closed position, whereby said motorpurnp controlled by said pressure responsive valve operates as a brake to maintain the downward force exerted by gravity on the drill string substantially constant, and said control device actuated by said transmitter from open to closed position operates to control flow of liquid from said source through said relief valve to said motorpump to control the feed of said drill string in accordance with the torque applied to the drill string.

2. In a well drilling apparatus including a drill bit carried by a drill string, a rotary table for driving the drill string and means including a hoisting drum for raising and lowering the drill string, an apparatus for controlling the feed of the drill string in accordance with the force of gravity and the torque applied to the drill string through the rotary table, said control apparatus comprising a combination motor-pump drivingly connected to said drum and having an intake and discharge, a liquid tank connected to said intake, a pressure responsive valve connected to said discharge, a return pipe from said valve to said tank and a planetary reduction gear for driving said rotary table, said reduction gear having a housing mounted for pivotal movement in proportion to the torque applied to the drill through said rotary table, whereby said motorpump controlled by said pressure responsive valve operates as a brake to maintain the downward force exerted by gravity on the drill string substantially constant, said control apparatus further including control means connected to said motor-pump for controlling the operation thereof, and means disposed in the path of movement of said housing to actuate said control means for controlling the operation of said motor-pump and the feed of said drill string in accordance with the torque applied to the drill string.

3. An apparatus as defined in claim 2, in which said motor-pump includes an electric motor and in which the means to control the operation of said motor-pump in accordance with the torque applied to said drill string comprises, a hydraulic transmitter actuated by movement of said housing, a hydraulic relay connected to said transmitter and a switch actuated by said relay to control the operation of said electric motor.

4. An apparatus as defined in claim 2, in which said motor-pump includes an electric motor and in which the means to control the operation of said motor-pump in accordance with the torque applied to said drill string comprises a switch actuated by movement of said housing to control the operation of said electric motor.

5. In a well drilling apparatus including a drill bit carried by a drill string, a rotary table for driving the drill string and means including a hoisting drum for raising and lowering the drill string, an apparatus for controlling the feed of the drill string in accordance with the force of gravity and the torque applied to the drill string through the rotary table, said control apparatus comprising a combination of motor-pump drivingly connected to said drum and having an intake and discharge, a liquid tank connected to said intake, a pressure responsive hydraulic control device connected to said discharge and having an open and closed position, resilient means to bias said control device to open position, a pressure responsive valve connected to said control device through an inlet and outlet, said control device in open position providing communication between said discharge and said inlet to said pressure responsive valve, a return pipe from said control device to said tank, a pump connected to said tank providing a hydraulic pressure source, a conduit connecting said source and control device, a relief valve connected between said conduit and said discharge, said control device in closed position serving to close said conduit, whereby the resulting increased pressure in said conduit opens said relief valve to provide communication between said conduit and said discharge and means for driving said rotary table, whereby said motor-pump controlled by said pressure responsive valve operates as a brake to maintain the downward force exerted by gravity on the drill string substantially constant and means operative in response to the torque applied to said drill string to move said control device from open to closed position to control flow of liquid from said source through said relief Valve to said motorpump thereby controlling the feed of said drill string in accordance with the torque applied thereto.

6. An apparatus as defined in claim 5 in which the means for driving said rotary table comprises an electric motor, a solenoid connected in the circuit of said motor and a hydraulic transmitter actuated by said solenoid and connected to said control device to move said control device from open to closed position, whereby the operation of said control device is controlled in accordance with the torque applied to said drill string by said electric motor.

7. An apparatus as defined in claim 5, in which the means for driving said rotary table comprises an electric motor and means connected in the circuit of said electric motor to control the movement of said control device from open to closed position in accordance with the torque applied to said drill string by said electric motor.

References Cited in the file of this patent UNITED STATES PATENTS 1,804,779 Jones et al May 12, 1931 1,919,611 Besigk July 25, 1933 2,003,078 Hild May 28, 1935 2,136,356 Hild Nov. 8, 1938 2,582,217 OLeary Jan. 15, 1952 2,634,099 OLeary Apr. 7, 1953 FOREIGN PATENTS 456,447 Great Britain Nov. 6, 1936 

2. IN A WELL DRILLING APPARATUS INCLUDING A DRILL BIT CARRIED BY A DRILL STRING, A ROTARY TABLE FOR DRIVING THE DRILL STRING AND MEANS INCLUDING A HOISTING DRUM FOR RAISING AND LOWERING THE DRILL STRING, AN APPARATUS FOR CONTROLLING THE FEED OF THE DRILL STRING IN ACCORDANCE WITH THE FORCE OF GRAVITY AND THE TORQUE APPLIED TO THE DRILL STRING THROUGH THE ROTARY TABLE, SAID CONTROL APPARATUS COMPRISING A COMBINATION MOTOR-PUMP DRIVINGLY CONNECTED TO SAID DRUM AND HAVING AN INTAKE AND DISCHARGE, A LIQUID TANK CONNECTED TO SAID INTAKE, A PRESSURE RESPONSIVE VALVE CONNECTED TO SAID DISCHARGE, A RETURN PIPE FROM SAID VALVE TO SAID TANK AND A PLANETARY REDUCTION GEAR FOR DRIVING SAID ROTARY TABLE, SAID REDUCTION GEAR HAVING A HOUSING MOUNTED FOR PIVOTAL MOVEMENT IN PROPORTION TO THE TORQUE APPLIED TO THE DRILL THROUGH SAID ROTARY TABLE, WHEREBY SAID MOTORPUMP CONTROLLED BY SAID PRESSURE RESPONSIVE VALVE OPERATES AS A BRAKE TO MAINTAIN THE DOWNWARD FORCE EXERTED BY GRAVITY ON THE DRILL STRING SUBSTANTIALLY CONSTANT, SAID CONTROL APPARATUS FURTHER INCLUDING CONTROL MEANS CONNECTED TO SAID MOTOR-PUMP FOR CONTROLLING THE OPERATION THEREOF, AND MEANS DISPOSED IN THE PATH OF MOVEMENT OF SAID HOUSING TO ACTUATE SAID CONTROL MEANS FOR CONTROLLING THE OPERATION OF SAID MOTOR-PUMP AND THE FEED OF SAID DRILL STRING IN ACCORDANCE WITH THE TORQUE APPLIED TO THE DRILL STRING. 